The present invention relates to a method of estimating a function of a memory IC on a board of a device (hereinafter, referred to as a lower device), connected to a controller by a communication interface not especially specified, capable of receiving a control therefrom.
Hitherto, in order to estimate the IC function on a board of a lower device, a controller is connected to a communication interface of the lower device, simulated control software is activated on the controller, built-in software for the estimation of the memory IC function is downloaded from the controller to the lower device, and the controller gives an instruction to the built-in software for the estimation of the memory IC function on the lower device, thereby performing a separate function test and a competing function test combined with a plurality memory ICs on a plurality of memory ICs (Flash ROM, SRAM, SDRAM) installed on the board of the lower device.
In the competing function test of the memory ICs (Flash ROM, SRAM, SDRAM) installed on the board of the lower device, according to the built-in software for the estimation of the memory IC function on the lower device, however, the competing timing is fixed, namely, when a test of a memory IC of a predetermined size is finished, it is switched to a test of another memory IC, and accordingly, there is such a problem that a test of the actual competing timing occurring in real circumstances can not be realized. Therefore, there have been cases that failures after the shipment of the boards built in products.